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Natural sciences

Grade 4

Planet earth and the universe

Module 45

Stormy weather


Learning about stormy weather conditions

[lo 2.1, 3.1]

Stormy weather


What do you do when the weather is stormy? Tell the class about funny stories related to storms.

Dark clouds converge in the air. Heavy rains fall to the earth. Now and again there is a bright flash of lightning and we hear the roar of thunder. But what is actually happening?


The air is full of small dust particles. Water drops form around such dust particles and then form clouds together with millions of other drops.

Try the following:

Mark an empty bottle in mm and place it outside when it rains.


During a storm strong winds blow the small water drops that have formed around the dust particles, into the centre of the clouds where they bounce against each other. Each of the small particles of a cloud has either a positive or negative electrical charge. When the particles bump against each other the charges separate. The majority of the positive charges move to the top of the cloud and the negative charges move toward the bottom of the cloud. Lightning is a massive electrical spark in the cloud. This spark occurs when the negative charges in one cloud come into contact with the positive charges in another cloud or with the ground.


Thunder is the loud noise that you hear when warm air and cold air suddenly come together. When lightning brightens the sky, it also heats the surrounding air. When this hot air comes into contact with the cold air, a gigantic wave of moving air causes the clap of thunder.

Dangerous weather


This is a very strong wind that is caused when a front with cold and dry air comes into contact with warm, moist air. It causes a large black cloud in the air. The warm air rises rapidly and more warm air moves in below it to replace it. Sometimes the rising air begins to move in a spiral and a tornado develops. If a tornado reaches the ground, it causes incredible damage because it sucks up everything that it encounters on the ground into the air.


This is a very big storm that starts on the surface of tropical seas. It consists of a large quantity of wind and rain that begins to spin around its centre, which we call the “eye”. It moves forwards as it rotates and creates enormous waves that are very destructive.

Cut A4 sheets of paper into four (into quarters) to have one small sheet of paper for each learner in the class. Each learner must draw an aspect of the weather on his or her piece of paper. Work clearly and neatly. Stretch a washing line across the classroom and hang the drawings of the “weather conditions” from the line!


LEARNING OUTCOME 2 : CONSTRUCTING SCIENCE KNOWLEDGE The learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

Assessment Standard

We know this when the learner

2.1 recalls significant information.

LEARNING OUTCOME 3 : SCIENCE, SOCIETY AND THE ENVIRONMENT The learner will be able to demonstrate an understanding of the interrelationships between science and technology, society and the environment.

Assessment Standard

We know this when the learner

3.1 understands science and technology in the context of history and personal knowledge.

Questions & Answers

what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Natural sciences grade 4. OpenStax CNX. Sep 18, 2009 Download for free at http://cnx.org/content/col11096/1.1
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